Filling valve



Dec@ 19g 3950 QE. R. GAERTTNER ETAL, 2,534,965

FILLING VALVE Filed Aug. 17, 1949 Their` Attorney Asuch aProtuber-ance within theenvelope.

Patented Dec. 19, 1950 UNITE-o .STATES @PATENT oFF-1C.

FILLING VALVE Erwin R. Gaerttner and Max L. 1Yeater, Schene,c

tally, N. Y., assignors te GeneralElectrcCompany, a corporation o'f New York Application August 17, 1949, Serial No. 110,852

-pass through .the envelope into the chamber enclosed thereby, molecules of the ionizable gas will 'be ionized. Thereafter, if the chamber volume is suddenly increased, fthe temperature in the chamber will decrease and :droplets of condensa- -tion will be :formed aboutgthe ions which serve .as centers for such condensation. Thus, the passage of the ionizing radiations through the chamber will be marked by tracks ofionsabout 4.which 4condensation has `been formed. These tracks "may then ,be illuminated by visiblelight `projected through the transparent portion ofthe envelope and'viewed or photographed to provide `a permanent record Vof the phenomenon.

iInsuch apparatus considerable difficulty has been experienced in providingsuitable means for introducing .gases into the expansible chamber through an aperture in the enclosing envelope.

After the gases have been introduced and the apparatus is placed in operation to obtain tracks of ionizing radiation, it is vof prime importance athat the means utilized forintroducing the gases be lof such a-design and .have vsuch .a location that the operation of the apparatus is not deleteriously aiected. The envelope enclosing the chamber is, :as .mentioned heretofore, usually constructed of A transparent .material and, .therefore, the gas introducingmeansmust becapable :ofsealing/an aperturein material such as glass or plastic without .interfering with ,the .viewing or photographing of the .ion tracks. In 4Some instances, a magnetic field is oriented to traverse the chamber, and in such event, the gas yintroducing means .must be designed to avoid -distortionofthis eld. Moreover, irregular protuberances iWithin the envelope enclosing the lexpansible chamberwill cause turbuleneeof the .gas whenthe chamberis expanded toform dropletsabouttheions createdby the ionizing radia tion and, consequently, means employed for clos- `ingthe apertureinthe envelope must not present Furthermore, .in-order for accurate results to be obtainecLiitfisfessential that all impuritiessuch as :centers as well as ions.

dust .particles be absent .from the chamber '.because such impurities will serveras condensation Therefore, .such ...impurities mustlbe fremovedfrom thechamber and not introduced during the processof llingthe chamber with thenecessary. gases.

,In accordance .with the present invention, thesediiiiculties have been overcome by providing asmall .valve adapted toseal an ,aperturein the .transparent envelope of cloud .chamber ,apparatus. :In its normal position -this .valve .is

vmaintainedin a sealing locationbymeansroftan adjusting screw Apositioned exteriorly =o f .the

envelope. Whenitis desired to fill the chamber with gases, ydetachable means kforming ,an yenclosureand adapted-to be sealed to theiexterior of Ithe envelope about Athe adjustingscrew .may

-be employed .to vopen the .valve and .admitfgases into the chamber.

The features which it is desired to protect herein are pointedout with particularity in -the appended l claims. with-further. objects and-advantages thereof, may `bestbekunderstood by reference to the following description, taken in .connection .with .the ac- The invention .itself together companyingdrawing -in which AEig. 1 is aseo- Y tional view of simplified cloud chamber @apparatus in which the-invention may iindsui-table application; Fig. 2 is a .partial section .of the `valve portion of the linvention in its normal. sealing position; and Fig. 3 isa sectional .view illustrating the detachable means for admitting gases into the cloud chamber apparatus.

Referring Iparticularly .=to Fig. l there .is shown a simplified -cloud .chamber Vapparatus in .which an expansible chamber I `is defined by a .transparent glass or plasticcylinder 2, a cylindrical gasket 3, a circular transparent-glassor plastic plate-ll and a flexible diaphragm '5. Cylindrical gaskets andlexible diaphragm 15 mayconsist of deformable material such as natural ,onsynthetic rubber :in order that chamber J maybe maintained airtight.

For suitably 'supporting the .above .mentioned portions dening chamber l there is shown da cylindrical base member 6 Vhaving at its upper end an youtwardly extending flange .'l against lwhich the vlower surface of flexible diaphragm .5

bears. Bolts-members and fSattached toange l' serve tofforcelciamping member 4I), Whichm-ay cefcircularlysymmetrical, against -the upper surface of plate li, l thereby assuring the proper sealing of lchamber .L

To provide a meansof flexing vdiaphragmlt'v.for altering .the volume. of .chamber I .thereisshown a piston I2 having a shaft member I3 and a head member I4, the upper surface of which may be positioned against the lower surface of diaphragm 5. As indicated by the dotted lines, piston I2 may be moved upward thereby reducing the volume of chamber I. In this latter position gases introduced into the chamber I, in a manner to be hereinafter described, will be in a saturated state, but if piston I2 is moved suddenly downward into the position shown by the heavy lines, the volume of chamber I will be increased and droplets will be formed about condensation centers which are present in the chamber at the time. In order to facilitate the movement of piston I2, enclosure I5, defined in part by a flexible bellows I6 sealed to shaft member I3 and a flange I1, may be partially evacuated.

As mentioned heretofore, in order for the cloud chamber apparatus to be operated to obtain ion tracks, ionizable gases and condensible vapors must be introduced into chamber` I. However, after the gases have been introduced, and the ap- .paratus placed in operation, the chamber I must be maintained relatively airtight in order to secure the proper pressure variations within chamber I. To provide suitable sealing means, there is shown in Fig. 2 a valve I8 which in its normal Vposition is adapted to seal an aperture I9 in glass plate 4 shown in Fig. l. The valve comprises a threaded stem 2D, inserted through aperture I9, and a head 2I attached to stem 28 and positioned within chamber I. A gasket 22 of deformable 'materiaL such as natural or synthetic rubber, is

positioned about stem 28 against the head 2 l. A cylindrical adjusting screw 23, having inner and outer threads, is placed with its inner threads engaging the threaded portion of stem 2f! such that its lower end may bear against the outer surface of glass plate 4 and force head 2B and gasket 22 upward to seal aperture I9.

In order to provide means for operating valve I8 to admit gases to chamber I, there is shown in Fig. 3 a threaded member 24 adapted to engage the outer threads of the adjusting screw 23 and to force a helical spring member 25 against a notched washer 26 which is supported by the outer surface of plate 4. A sleeve 21, supported by flange 28 and a fixed support 29, may be sealed to the exterior of plate 4 by means of a cylindrical gasket 30. A threaded thumb screw 3I may f be employed to hold sleeve 21 against support 29 and in sealing position on the outer surface of vplate 4.

Freely movable within the bore of sleeve 21 is a plunger 32 which has an upper boss 33 and a lower boss 34 serving to guide the movement within sleeve 21. Lower boss 34 may have aper- I tures 35 and 36 in order to facilitate the passage of gases therethrough into or from chamber I in a manner to be more fully described hereinafter. Plunger 32 may be sealed within sleeve 21 by means of a flexible diaphragm 31 clamped between blocks 38 and 39 which are held together by screw members 48 and 4I. Block 38 may be sealed to sleeve 21 in a conventional manner,

, outer surface of diaphragm 31 opposite the upper surface of plunger 32. Screw member 45, which engages a tapped hole in plate 46 secured to block 39, serves to hold washer 44 in place against the upper surface of diaphragm 31 by means of a tip 41 which turnably engages the notch in washer 44 to determine its position.

In Fig. 3 the means for operating valve I8 is shown in position to open valve I8 to admit gases into chamber I. Assuming that valve I8 is in the position shown in Fig. 2 the means for operating the valve may be assembled in the following manner. Washer 26, spring 25 and threaded member 24 may be positioned about adjusting screw 23 such that spring 25 is placed in compression. Adjusting screw 23 may then be turned to move its lower end a suitable distance away from the exterior of plate 4. It will be apparent that head 2l and gasket 22 will still be retained against the inner surface of plate 4 because of the force of Spring 25 and hence the sealing of aperture I9 is not affected.

After adjusting screw 23 has been moved away from the outer` surface of plate 4, sleeve 21, along with plunger 32, may be positioned in sealing relation against outer surface of plate 4 about washer 28, spring 25, adjusting screw 23, stem 28, and threaded member 24. Thereupon, screw member 45 may be turned to force plunger 32 downward such that the lower` surface of boss 34 will bear against the upper end of adjusting screw 23 and force stem 20 downward to open valve I8. It is to be presumed, however, that prior to the opening of valve I8, sleeve 21 will have been evacuated or lled with gases through a connection 48 which may be sealed to sleeve 21 in a convenient position along its bore. In the event that sleeve 21 is evacuated through connection 48, it should be observed that the force of spring 25 must be greater than the hydrostatic force on diaphragm 31 in order to prevent premature opening of valve I8.

While the invention has been described with particular reference to its advantageous application in cloud chamber apparatus, it will be apparent to those skilled in the art that the invention may nd similarly advantageous application in other forms of apparatus. L aim in the appended claims, therefore, to cover such equivalent variations of use and structure which come within the true spirit and scope of the foregoing disclosure.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. An envelope having an aperture through which gases may be admitted, a valve positioned L normally to seal said aperture comprising a stem member extending through said aperture, a head member attached to the end of said stem within said envelope, a gasket fitting about said stem against said head member, a cylindrical adjusting screw having inner and outer threads, said inner threads engaging threads on the outer end of said stem whereby said gasket may be forced against the inner wall of said envelope, detachable means for operating said valve to admit gases into said envelope comprising a helical spring member positioned about said adjusting screw and having one end attached to a threaded member adapted to engage the outer threads of said adjusting screw whereby said spring member may be placed in com-pression and said adjusting screw may be moved outward with respect to said envelope without moving said stem, and means forming an enclosure adapted to be sealed to the exterior of Said envelope about said spring member for forcing said adjusting screw inwardly whereby said valve may be opened to admit gases into said envelope.

2. An envelope having an aperture through which gases may be admitted, a filling valve adapted in a normal position to seal said envelope and in an operating position to admit gases into the envelope comprising a stem extending through the aperture in said envelope, a head member attached to the end of said stem within said envelope, a gasket of deformable material tting about said stem against said head member, a cylindrical adjusting screw having inner and outer threads, said inner threads engaging threads on the outer end of said stem whereby said gasket may be positioned against the inner wall of said envelope to seal the aperture in a normal position, detachable means for operating said valve to admit gases i-nto said envelope comprising a helical spring member positioned about said adjusting screw, a threaded member engaging. the outer threads of said adjusting screw and bearing against said spring member whereby said spring member may be placed in compression and said adjusting screw may be moved outward with respect to said envelope without moving said stem, and means forming an enclosure sealed to the exterior of said envelope about said spring member for forcing said adjusting screw inwardly whereby said valve may be opened to admit gases into said envelope.

3. In apparatus for the detection of ionizing radiation having an envelope of variable volume in which gases may be expanded to form condensation droplets about ions created by the passage of radiation through the envelope, a filling valve adapted in a normal position to seal the envelope and in an operating position to admit gases into the envelope comprising a stem tting loosely through an aperture within a wall of the envelope, a head member attached'to the end of said stem within the envelope, a gasket of deformable material fitting about said stem against said head member, a cylindrical adjusting screw having inner a/nd outer threads, said inner threads engaging threads on the outer end of said stem whereby said gasket may be positioned against the inner wall of the envelope to seal the aperture, detachable means for operating said valve to admit gases into the envelope comprising a helical spring member positioned about said adjusting screw, a threaded member engaging the outer threads of said adjusting screw and bearing against said spring member whereby said spring member may be placed in compression and said adjusting screw may be moved outward with respect to the envelope without moving said stem, a sleeve about said spring member adapted to be sealed to the wall of the envelope, and a plunger sealed within saidsleeve, said plunger being externally movable to force said adjusting screw, said stem. said head and said gasket inwardly against the force of said spring member whereby said valve may be opened to admit gases introduced into said sleeve into the envelope.

ERWIN R. GAER'I'INER. MAX L. YEATER.

No references cited. 

